SV Gastrointestinal Alterations Slides - Tagged

Overview of Gastrointestinal (GI) Function Alterations

Gastrointestinal alterations can arise from various problems affecting muscle function, nerve-triggering capabilities, or physical obstructions. These issues can lead to deficient digestion and/or absorption due to several underlying causes:

  • Problems with enzymes or their secretion
  • Problems with the absorptive surfaces of the GI tract
  • Other conditions affecting the GI system include abnormalities of blood supply, inflammation, and tumors.

Congenital Defects

Pyloric Stenosis

Pathophysiology
  • Pyloric stenosis involves thickening and stiffness of the pyloric sphincter muscle fibers, resulting in narrowing or blockage of the pyloric sphincter. This condition significantly impedes the stomach's ability to empty food into the small intestines.
Risk Factors
  • Pyloric stenosis is the most common cause of GI obstruction in infancy, with symptoms typically emerging around 3 weeks of age, and is rare after 6 months.
Clinical Manifestations
  • Symptoms include:
      - Hard olive-shaped mass in the right upper quadrant (RUQ) of the abdomen
      - Projectile vomiting after feeding
      - Wave-like stomach contractions
      - Persistent hunger despite feeding
      - Failure to gain weight
Complications
  • One major complication is malnutrition.

Cleft Lip & Palate

Pathophysiology
  • Cleft lip results from the failure of the maxillary processes and nasal elevations or upper lip to fuse during fetal development.
  • Cleft palate arises from the failure of the hard and soft palate to fuse.
  • Causes are multifactorial, including genetic disorders, maternal drug toxicity, infections, vitamin deficiencies, smoking, and diabetes.
Risk Factors
  • Higher incidence in individuals of Native American, Hispanic, and Asian descent, with males being more likely to have cleft lip and females more likely to have cleft palate.
Clinical Manifestations of Cleft Lip
  • Complexity of cleft lip can range from a small notch to a complete split, and may be unilateral or bilateral.
  • Complications: Possible feeding/eating difficulties, speech difficulties.
Clinical Manifestations of Cleft Palate
  • Characterized by an opening between the oral and nasal cavity, malformations of teeth and nasal structures, and potential choking during feeding.
  • Complications: High aspiration risk, feeding difficulties, nutritional deficits, speech difficulties, ear infections, and hearing problems.

Disorders of the Upper GI Tract

Dysphagia

Pathophysiology
  • Dysphagia refers to difficulty swallowing, which can be associated with pain and can vary in severity. It can manifest in several ways, including an inability to swallow solid pieces or liquids.
Causes
  • Neurologic conditions: brain damage, infections, muscular nerve damage (e.g., in conditions like Parkinson's, muscular dystrophy, or multiple sclerosis).
  • Mechanical obstructions can also cause dysphagia.
Clinical Manifestations
  • Common symptoms include:
      - Sensation of something stuck in the throat
      - Coughing or choking during/after swallowing
      - Delayed or painful swallowing
      - Facial paralysis or issues with head control
Complications
  • Severe risks include aspiration pneumonia, dehydration, malnutrition, prolonged disability, and increased mortality.

Vomiting (Emesis)

Pathophysiology
  • Vomiting is characterized by the involuntary or voluntary forceful ejection of chyme from the stomach through the esophagus and out of the mouth, known as reverse peristalsis. The vomiting center in the brain (medulla) coordinates this action.
Etiologies/Causes
  • Vomiting can arise from various disease processes or treatments (e.g., after chemotherapy or surgery) and can be protective, removing toxins.
  • It is also linked to increased intracranial pressure and mechanical obstructions.
Clinical Manifestations
  • Common presentations:
      - Presence of partially digested food in vomitus
      - Hematemesis (blood in vomitus) can appear bright red or as coffee grounds; indicates upper GI bleeding.
      - Projectile vomiting often accompanies increased intracranial pressure.
Complications
  • Potential issues include dehydration, electrolyte imbalances, aspiration pneumonia, and increased mortality.

Hiatal Hernia (HH)

Pathophysiology
  • A hiatal hernia occurs when a portion of the stomach protrudes through an opening in the diaphragm into the thoracic cavity. The hernia can be small or large due to the weakness in the diaphragm or pressure changes in the abdomen.
Risk Factors
  • Common contributors include smoking, advanced age, and increased abdominal pressure due to obesity or trauma.
Clinical Manifestations
  • Symptoms often involve indigestion, heartburn, belching, nausea, and abdominal pain. Severe cases may develop into gastroesophageal reflux disease (GERD).

Gastroesophageal Reflux Disease (GERD)

Pathophysiology
  • GERD occurs when stomach contents flow back into the esophagus due to a malfunctioning lower esophageal sphincter.
Risk Factors
  • Contributing factors include obesity, pregnancy, alcohol consumption, certain foods, and medications.
Clinical Manifestations
  • Patients experience heartburn, epigastric pain, nausea, vomiting, and may present with laryngitis or a sensation of a lump in the throat.
Complications
  • Serious complications include esophagitis, esophageal strictures, and potential progression to esophageal cancer.

Gastritis

Pathophysiology
  • Gastritis refers to inflammation with breaking down of the gastric mucosal barrier.
Risk Factors
  • Factors leading to gastritis can include long-term NSAID use, autoimmune disorders, lifestyle factors (smoking, alcohol), and dietary habits.
Clinical Manifestations
  • Symptoms may include indigestion, nausea, vomiting, and abdominal pain, with acute and chronic presentations differing in severity.
Classification
  • Acute gastritis: Often milder and self-limiting, or severe with potential for GI bleeding.
  • Chronic gastritis: Associated typically with Helicobacter pylori infection, which can lead to peptic ulcers or anemia through interference with nutrient absorption.

Disorders of Lower GI Tract

Intestinal Obstruction

Pathophysiology
  • Interference with normal peristalsis leads to accumulation of fluids, gasses, and contents proximal to the blockage, causing distention and potential rupture if left untreated.
Types
  • Obstructions can be classified as:
      - Mechanical: involving physical barriers like tumors or strangulated hernias.
      - Functional (Ileus): due to impaired peristalsis from medications or neurological injuries.
Clinical Manifestations
  • Patients may present with colicky abdominal pain, distention, nausea, vomiting, constipation or diarrhea, and potentially shock from severe complications.
Complications
  • Complications can include bowel perforation, pH imbalances, fluid/electrolyte disturbances, and infection.

Appendicitis

Pathophysiology
  • Inflammation of the appendix commonly results from obstruction by hardened fecal matter leading to proliferation of bacteria, edema, ischemia, and potential necrosis.
Risk Factors
  • Commonly seen in individuals aged 10-12 years and linked to diets low in fiber.
Clinical Manifestations
  • Patients often experience sharp abdominal pain initially in the umbilical area progressing to the RLQ, along with fever, leukocytosis, nausea, and rebound tenderness.

Peritonitis

Pathophysiology
  • Inflammation of the peritoneum due to perforation of abdominal organs leading to the release of bacteria and gastro-intestinal contents into the peritoneal cavity.
Risk Factors
  • Surgical enterance/complications, perforated organs, and leakage of infected fluid into peritoneal space.
Clinical Manifestations
  • Classic signs include abdominal pain, rigidity ('board-like abdomen'), rebound tenderness, along with general systemic symptoms such as fever and malaise.

Cancers of the GI Tract

Overview

  • Gastrointestinal cancer encompasses various types including esophageal, liver, pancreatic, colorectal, and cancers affecting other parts of the digestive system. It is one of the most prevalent forms of cancer and poses a significant health risk worldwide.

Esophageal Cancer

Pathophysiology
  • Primarily occurs in the distal esophagus as either squamous cell carcinoma or adenocarcinoma, often linked to chronic irritation.
Risk Factors
  • Factors include chronic GERD, smoking, alcohol consumption, and being male over the age of 45.
Clinical Manifestations
  • Early signs may present as dysphagia, chest pain, weight loss, worsening indigestion, and halitosis.

Pancreatic Cancer

Pathophysiology
  • An aggressive form of cancer primarily presenting with an adenocarcinoma; it often goes unnoticed until advanced due to lack of early symptoms and rapid metastasis.
Clinical Manifestations